Add-On Back-Up Lighting

I'm trying to add a pair of Fog Lights to my Reverse Lights in an attempt to enhance visibility behind my car.

Can someone describe the proper contacts on the RELAY for this upgrade?

I've tried:

30 > 12v Battery Power (+)

85 > Tapped into Factory wire for Reverse (+)

86 > Ground (-)

87 > Fog Light (+)

87A > Nothing

In this order,... I can't seem to get it to work. -I need the lights to go on when I put the car into reverse (only) and, not when I am driving  :oops:

--SYAO

You guys are right,... using the factory reverse wire to power the lights does work but then,... the factory reverse lights are only running at half or diminished output; I can only assume the add-on lights would also be running at diminished output as well  :o(

I think,... a RELAY is my only option to power both OEM & PIAA 1500XT's at FULL power. --Maybe I need two?

Since his connections are correct to the SPDT I can only think of two possibilities:

1) The SPDT is bad and needs to be replaced or,

2) The SPDT is rated for less than 10 amps and both lights are tapping too much energy through it. (most likely burned it out)

If you want to run OEM and the PIAAs you will need an SPDT rated higher than that. If I am not mistaken the PIAAs take about 12 amps on them, so I would use a 15 or 20 amp relay. If you want to maintain brightness, then you will need the relays.

Hope this helps. Ganbatte ne (good luck -or- do your best)